Moyamoya disease is characterized by progressive stenosis of the intracranial ICAs and their proximal branches. This results in the limited supply of blood flow in the major vessels of anterior circulation, which consecutively leads to the development of collateral circulation, by the small vessels. The posterior circulation involvement in moyamoya disease has not been well studied.[1] This process may rarely involve posterior circulation also, including the basilar cerebral arteries and PCAs.[2] The PCA if involved mainly affects the distal portion.[3] This is because of posterior circulation behaves as collateral pathway for maintenance of the circulation. The posterior circulation involvement is an adverse prognostic factor for outcome in moyamoya disease.[4] A study from India reported the absence of posterior circulation involvement in case series of 44 patients.[5] The ischemic episodes are rare in the posterior circulation territory till the late phase in moyamoya disease.[6] Development of extensive collateral vasculature results in the angiographic appearance of “puff of smoke” which is considered as a hallmark of the disease. The MRA and CTA images shown here depict the classical “puff of smoke” appearance and thus will serve as an excellent learning resource for medical graduates and postgraduates to understand the basic pathophysiology of the disease.